Method and composition for the removal of ascorbic acid from aqueous liquids

Abstract

The present invention provides a process for removing ascorbic acid from aqueous solutions by the addition of ascorbate oxidase, wherein catalase and hydrogen peroxide are also added to the solution. The present invention also provides an agent for the removal of ascorbic acid from aqueous solutions, based on a solid carrier material impregnated with ascorbate oxidase, wherein the carrier material also contains catalase and hydrogen peroxide and optionally also a stabilizer and/or buffer substance.

What is claimed is: 
     
       1. Process for removing ascorbic acid from an aqueous solution containing same which process comprises adding to the aqueous solution, ascorbate oxidase, catalase and hydrogen peroxide, the catalase being added simultaneously with, or prior to the addition of hydrogen peroxide. 
     
     
       2. Process as claimed in claim 1 wherein the hydrogen peroxide is used in the form of a hydrogen peroxide-containing adduct. 
     
     
       3. Process as claimed in claim 2 wherein said adduct is a perborate. 
     
     
       4. Process as claimed in claim 2 wherein said adduct is a urea perhydrate. 
     
     
       5. Process as claimed in claim 2 wherein said adduct is a mannitol perhydrate. 
     
     
       6. Reagent for the removal of ascorbic acid from aqueous solutions comprising a solid carrier material impregnated with ascorbate oxidase, wherein the carrier material also contains catalase and hydrogen peroxide. 
     
     
       7. Reagent as claimed in claim 6 wherein said carrier material additionally contains a stabilizer. 
     
     
       8. Reagent as claimed in claim 7 wherein said stabilizer is pectin, polyvinylpyrrolidone or dextran, or mixtures thereof. 
     
     
       9. Reagent as claimed in claim 6 wherein said carrier material additionally contains a buffer substance. 
     
     
       10. Reagent as claimed in claim 6 wherein said carrier material contains the ascorbate oxidase and the catalase together and the hydrogen peroxide physically separated therefrom. 
     
     
       11. Reagent as claimed in claim 6 wherein said hydrogen peroxide is present as a solid adduct. 
     
     
       12. Reagent as claimed in claim 6 wherein said carrier material consists of the first compact carrier material to which is fixed at least one second porous absorbent carrier material which is impregnated with one or more of the active materials. 
     
     
       13. Reagent as claimed in claim 12 wherein the first carrier material is in the form of a strip or rod. 
     
     
       14. Reagent as claimed in claim 12 wherein the first carrier material consists of glass or synthetic resin. 
     
     
       15. Reagent as claimed in claim 12 wherein the second carrier material is a paper or fleece. 
     
     
       16. Reagent as claimed in claim 6 wherein said carrier material contains a buffer substance which is effective at a pH value of from 5 to 8.5. 
     
     
       17. Reagent as claimed in claim 16 wherein said buffer substance is tris-citrate or tris-citric acid buffer. 
     
     
       18. Reagent as claimed in claim 16 containing at least 30 U of ascorbate oxidase. 
     
     
       19. Reagent as claimed in claim 18 containing 35 to 40 U of ascorbate oxidase.